First results on early post-fire succession in an Abies cephalonica forest (Parnitha National Park, Greece)

Due to climate changes, the interest in the post-fire recovery of forest communities not adapted to wildfires, such as Greek fir (Abies cephalonica) forests, has increased. In this study, the post-fire recovery of the burned A. cephalonica forest of Parnitha National Park (central Greece) was investigated after a stand-replacing fire occurred in summer 2007, as well as the performance of A. cephalonica plantings in the post-fire conditions. The research focused on the estimation of the A. cephalonica stand reproductive capacity without fire, the evaluation of the post-fire regeneration of the burned stands, and the monitoring of the plantations performance after the fire in the area. Then, based on the field and laboratory data, the post-fire recovery process of A. cephalonica was evaluated by application of a simplified form of the comprehensive causal framework for ecological succession estimation in open site, developed by Pickett et al. (1987), adapted to the study conditions. According to the findings of the study, stand seed crop without fire was high, while seed quality was found extremely low. In the burned area, no A. cephalonica seedling recruitment was observed during the three years after the fire. A. cephalonica plantings exhibited a medium overall survival rate (65.3%), while seedlings growth was very slow. Thus, we can suppose that an ecological succession process may occur in the burned area, if no human interventions applied, and species adapted to wildfires (mainly shrubs and herbaceous) will dominate in the area. However, planting of A. cephalonica seedlings could contribute to the species participation in the post-fire communities

Speciation and historical migration pattern interaction: examples from P. nigra and P. sylvestris phylogeography

Here, from macrophylogeographic mtDNA empirical data, we propose a scenario for the evolution and speciation of two important forest trees, European black pine and Scotch pine, and their multiple subspecies and varieties. Molecular clock simulations revealed that INDEL variability in the Pinus mitochondrial genome is relatively old, i.e., from the Pliocene-Miocene epoch, and related to historical tectonic continental fluctuations rather than to climate change at a large geographic scale. For conservation and management biodiversity program recommendations, special attention is given to the relationships between different speciation models, historical migration patterns, and differences between peripheral and central populations. Species evolution involves the mixing of different speciation modes, and every speciation mode has different effects on different DNA types (e.g., mitochondrial vs. chloroplast vs. nuclear DNA). The misbalance between the contributions of different meta-population census sizes vs. effective population sizes to asymmetric migration patterns is the result of different genotypes (and subphylogenetic lines) responding to selection pressure and adaptive evolution. We propose initial minimal size of conservation unit (between 3 and 5 ha) from central and marginal natural area of distribution for both species in the dynamic management system for practical forest genetic diversity management. The proposed physical sizes were determined by the effective population size, effective radius of seed distribution data, forest density age dynamics, succession pattern, natural selection pressing and species biology [R-17]

Ancient genetic bottleneck and Plio-Pleistocene climatic changes imprinted the phylobiogeography of European Black Pine populations

<p>The historical changes in European Black Pine population size across the whole natural distribution in Europe and Asia Minor were analyzed facing the Plio-Pleistocene climatic fluctuations. Thirteen chloroplast SSRs and SNPs markers have been studied under the assumptions of “neutral evolution.” Populations and meta-populations had different histories of migration routes, and they were strongly affected by complex patterns of isolation, fragmentation, speciation, expansion (1.88–4.28 Ma), purification selection (2.09–21.41 Ma) and bottleneck (1.85–21.76 Ma). A significant number of populations (min. 29–41%) were in equilibrium for very long periods. Generally, the bottleneck revealed by chloroplast DNA is weaker than the bottleneck revealed by nuclear DNA. The N_e immediately after the bottleneck reaches between 1820 and 3640 individuals. Generally, the historical effective population sizes shrink significantly for the Tertiary period from 10–15 up to 2.5 Ma in Western Europe (by 82%), followed by Asia Minor (69%) and the Balkan Peninsula (28%), likely resulting from important climatic changes. The rates and frequencies of stepwise westwards migration waves have been not sufficient to prevent isolation between the meta-populations and to suppress “sympatric speciation.” The migration was weak for the Pliocene, but was maximal for the Pleistocene, and finally silent for the present interglacial period, namely the Holocene.</p

Ancient split of major genetic lineages of European Black Pine: evidence from chloroplast DNA

International audienceThe European Black Pine (Pinus nigra Arn.) has a long and complex history. Genetic distance and frequency analyses identified three differentiated genetic groups, which corresponded to three wide geographical areas: Westerns Mediterranean, Balkan Peninsula and Asia Minor. These groups shared common ancestors (14.75 and 10.72 Ma). The most recent splits occurred after the Messinian Salinity Crisis (4.37 Ma) and the Early–Middle Pleistocene Transitions (0.93 Ma). The posterior ancestral population size (Na) is 260, 000–265,000 individuals. Each pool is further fragmented, with evidence of a phylogeographic structure (Nst > Gst) typ- ically observed in some natural populations from the Western Mediterranean region and the Balkan Peninsula. The labora- tory analysis was performed by fragment analysis—i.e. elec- trophoretic sizing of polymerase chain reaction fragments, combined with the sequencing analysis of 33 % of all individ- uals as a control. Intense sampling of chloroplast DNA poly- morphisms (3154 individuals and 13 markers: SNPs and SSRs) over the full area of the species’ natural distribution indicated moderate among-population variability (Gst(nc) ≤ 0.177) in various parts of its range. These results indicate that the natural populations have long migration his- tories that differ from one another and that they have been strongly phylogeographically affected by complex patterns of isolation, speciation and fragmentation. Long and varying climatic fluctuations in the region of the principal genetic group have been the probable cause of different forest com- munity associations with different successional patterns resulting in interglacial refugia vs. macro long-term refugia

Ancient genetic bottleneck and Plio-Pleistocene climatic changes imprinted the phylobiogeography of European Black Pine populations

<p>The historical changes in European Black Pine population size across the whole natural distribution in Europe and Asia Minor were analyzed facing the Plio-Pleistocene climatic fluctuations. Thirteen chloroplast SSRs and SNPs markers have been studied under the assumptions of “neutral evolution.” Populations and meta-populations had different histories of migration routes, and they were strongly affected by complex patterns of isolation, fragmentation, speciation, expansion (1.88–4.28 Ma), purification selection (2.09–21.41 Ma) and bottleneck (1.85–21.76 Ma). A significant number of populations (min. 29–41%) were in equilibrium for very long periods. Generally, the bottleneck revealed by chloroplast DNA is weaker than the bottleneck revealed by nuclear DNA. The N_e immediately after the bottleneck reaches between 1820 and 3640 individuals. Generally, the historical effective population sizes shrink significantly for the Tertiary period from 10–15 up to 2.5 Ma in Western Europe (by 82%), followed by Asia Minor (69%) and the Balkan Peninsula (28%), likely resulting from important climatic changes. The rates and frequencies of stepwise westwards migration waves have been not sufficient to prevent isolation between the meta-populations and to suppress “sympatric speciation.” The migration was weak for the Pliocene, but was maximal for the Pleistocene, and finally silent for the present interglacial period, namely the Holocene.</p

Ancient genetic bottleneck and Plio-Pleisocene climatic changes imprinted the phylobiogeography of European Black Pine populations

The historical changes in European Black Pine population size across the whole natural distribution in Europe and Asia Minor were analyzed facing the Plio-Pleistocene climatic fluctuations. Thirteen chloroplast SSRs and SNPs markers have been studied under the assumptions of “neutral evolution.” Populations and meta-populations had different histories of migration routes, and they were strongly affected by complex patterns of isolation, fragmentation, speciation, expansion (1.88–4.28 Ma), purification selection (2.09–21.41 Ma) and bottleneck (1.85–21.76 Ma). A significant number of populations (min. 29–41%) were in equilibrium for very long periods. Generally, the bottleneck revealed by chloroplast DNA is weaker than the bottleneck revealed by nuclear DNA. The N e immediately after the bottleneck reaches between 1820 and 3640 individuals. Generally, the historical effective population sizes shrink significantly for the Tertiary period from 10–15 up to 2.5 Ma in Western Europe (by 82%), followed by Asia Minor (69%) and the Balkan Peninsula (28%), likely resulting from important climatic changes. The rates and frequencies of stepwise westwards migration waves have been not sufficient to prevent isolation between the meta-populations and to suppress “sympatric speciation.” The migration was weak for the Pliocene, but was maximal for the Pleistocene, and finally silent for the present interglacial period, namely the Holocene.This is a post-peer-review, pre-copyedit version of an article published in European Journal of Forest Research. The final authenticated version is available online at: [http://dx.doi.org/10.1007/s10342-017-1069-9